Gas blast actuated auxiliary turbine for gas blast propelled craft



Oct. 12, 1948. R. H. GODDARD GAS BLAST ACTUATED AUXILIARY TURBINE FOR GAS BLAST PROPELLED CRAFT Filed June 11, 1945 5 Sheets-Sheet l Oct. 12, 1948. R. H. GODDARD 2,450,950

GAS BLAST ACTUATED AUXILIARY TURBINE FOR GAS BLAST PROPELLED CRAFT.

Filed June 11. 1945 5 Sheets-Sheet 2 23 w 23 D 1 90 W I WI? 1 1 1 Z3 \zgg'y/ I 50 Oct. 12, 1948. R. H. GODDAR 2,450,950

GAS BLAST ACTUATED AUXILI TURBINE FOR GAS BLAST PROPELLED CRAFT Filed June 11, 1945 5 Sheets-Sheet 3 0d. 12, 1948. R, GODDARD 2,450,950

GAS BLAST ACTUA'IED AUXILIARY TURBINE 1 FOR GAS BLAST PROPELLED CRAFT Filed June 11. 1945 5 Sheets-Sheet 4 1a. 63- I ma Gct. 12, 1948.

R. H. GODDARD 2,450,950 GAS BLAST ACTUATED AUXILIARY TURBINE FOR GAS BLAST PROPELLED CRAFT Filed June 11. 1945 5 Sheets-Sheet 5 Bessure-Eadac/n A Wye I 1 Bax-sure 750k 50/ a-a f Patented-Oct. 12, 1948 GAS BLAST ACTUATED AUXILIARY TUR- BINE FOR GAS BLAST PBOPELLED CRAFT obert H. Goddard, Annapolis, Md.; Esther C. 'Goddard executrix of said Robert H. Goddard.

deceased, assignor of one-half to The Daniel and Florence Guggenheim Foundation, New York, N. Y., a corporation of New York Application June 11, 1945, Serial No. 598,755

9 Claims. 1

This invention relates to improvements in auxiliary power devices for gas blast propelled craft and particularly to means for utilizing a portion of the rocket propulsion blast for driving pumps for supplying combustion materials to the rocket motor, together with auxiliary means for starting and controlling the operation of the pumps.

It hasbeen found that turbines actuated by a small portion of the blast from a rocket motor provide a comparatively simple and effective means for operating pumps for supplying fuel and oxidant to the motor. The pump turbines require but a small portion of the horsepower of the rocket jet, the mechanical power of which is very great owing to the extremely high velocity of the blast. Even the part of the blast that is used,

however, may be utilized in such a way that a maximum of power is obtained for a minimum reduction in thrust and, in addition, the resulting fuel economy is greater the higher the velocity of the portion of the blast that is used.

In general, the turbine-pump combination of the invention comprises one or more turbines positioned to be impelled in normal operation by the external portion only of a rocket motor blast, together with means for guiding the turbine driving gases into the direction of maximum effective thrust, means for varying the turbine thrust by varying the position of the turbine in the blast,

vision of rocket blast driven turbines adapted to utilize to a high degree the residual momentum in the gases leaving theturbines.

Another object of the invention is to provide a rocket blast driven turbine-pump combination which will be largely self-regulating.

Another object of the invention is to provide a rocket blast driven turbine-pump construction which will have little or no thrust on the bearings. Y

,Another object of the inventionis to provide means for effectively controlling the operation gt a rocket blast driven turbine-pump combinaion.

A further object of the invention is to provide means for starting the pumps of a rocket blast driven turbine-pump combination.

A further object of the invention is the provision of means for directing all or a major portion of the rocket blast gases into the rocket blast driven turbinesduring the starting period to obtain relatively high power from the turbines at low rocket blast velocities.

These and other objects and advantages of the invention will be more clearly apparent fromthe following detailed descriptions of illustrative embodiments of the invention with reference to the accompanying drawings in which:

Fig. 1 is a fragmentary front end portion in partial section of a rocket craft including a rocket blast driven turbine-pump construction embodying the principles of the invention;

Fig. 2 is a transverse view in partial section on line 22 of Fig. 3 of the turbine-pump as-' sembly of Fig. 1;

- Fig. .3 is an elevation from the turbine end of v Fig. 6 is an enlarged fragmentary viewof blade members of the turbine of Fig. 5; I

' Fig. '7 is a fragmentary sectional view on lines 1-4 of Fig. 6; I

Fig. 8 is a perspective view of the blast guide member of Figs. 1 to 4;

Fig. 9 is a sectional elevation of the guidem'ember of Fig. 8;

Fig. 10 is an enlarged fragmentary sectional view of a detail of the guide member of Figs. 8 and 9;

Fig. 11 is a fragmentary view in partial section showing the thrust, compensating construction of the turbine-pump assembly;

Fig, 12 is a transverse sectional view on line Figs. 13 and 14 are diagrammaticrepresentations of modified embodiments of the thrust control construction of the invention;

Fig. 15 is a view in sectional elevation of a pump pressure control valve;

Fig. 16 is a view in partial section of the pump pressure control assembly;

Fig. 16a is a fragmentary view showing the details of a control valve useful in the pressure control assembly of Fig. 16;

Fig. 17 is a semi-diagrammatic representation of a starting device of the invention;

Fig. 18 is a semi-diagrammatic representation of another form of starting device;

Fig. 19 is a semi-diagrammatic representation of a device for increasing the blast flow to the turbines during the period of relatively low blast velocity;

Fig. 20 is a perspective view of the blast guide member of Fig. 19;

Fig. 21 is a fragmentary view showing a modifled turbine-pump assembly;

Fig. 22 is a fragmentary view showing a modifled arrangement of the .blast motors and turbinepump assemblies;

Fig. 23 is a. plan view in partial section showing an end thrust compensated turbine-pump assemb y;

Fig. 24 is a diagrammatic radial view of the blades of the turbine of Fig. 23, and

Fig. 25 is an enlarged sectional view of the solenoid operated valve of Fig. 23.

A typical embodiment of the turbine-pump assembly of the invention is shown generally in Figs. 1-3. In Fig. 1 the turbine-pump assembly is shown in association with rocket motors I mounted in recesses II in the forward or head end of a rocket craft l2. For the sake of clarity only two of a group of four symmetrically positioned rocket motors are shown.

The assembly comprises paired turbines l3, l3 and pumps 14, i4. Each turbine and its associated pump are mounted on a common shaft 15. Typically one pump of each pair in the assembly supplies fuel and the other pump oxidant to the rocket motor i0 through conduits [6. The combustion material flows to the pumps through conduits l1 leading to tanks, not shown, which may conveniently be mounted in the rocket as described in my U. S. Patent No. 2,109,529.

Each turbine-pump combination is mounted upon abase l8 by means of a thin web 40 connecting the base and bearing housing 41. The base 3 is pivotally supported at H! upon a suitable pintle 20 extending from the rocket structure. Between the bearing housing and the turbine the haft passes through block 42 the purpose of which is more fully described hereinafter.

The preferred form of turbine, as shown in Figs. l-3 and in enlarged detail in Fig. 4, comprises a disk 2| having a rather wide rim for-med by the hollow turbine blades 22. The blades 22 are shaped to direct that portion of the blast which engages the turbine blades laterally away from the turbine disk to each side thereof. As shown particularly in Figs. 1 and 4, the vanes are each curved to engage a substantial portion of half the periphery of the blast. By providing paired turbines engaging opposite sides of the blast, the blast is effected much less than by a single turbine on one side taking the same power. By positioning and shaping the turbine blades to engage only the peripheral portion of the blast, they come in contact with the part of the blast of lowest velocity and of lowest temperature so that it is easier to maintain the blades at a safe operating temperature. This position of the blades also entails the least interference with the high velocity core of the blast.

The blades are preferably made of a material which maintains its strength at high temperatures, such as a suitable grade of stainless steel. They also are preferably made of uniform wall thickness to facilitate effective cooling as well as for the sake of lightness although they may be thickened adjacent the supporting disk to increase the resistance to bending under centrifugal force.

Since the vanes are in the rocket motor blast only for a small fraction of each revolution, typically for a tenth of a revolution or less, they normally will be cooled to a safe operating temperature by the atmosphere. However, if the blast is extremely hot or if the rocket operates at high altitudes where the cooling effect of the atmosphere is less due to its lower density, the vanes may be further cooled by introducing water or any suitable coolant from nozzles 23 adjacent each side of the disks. The coolant is caught in the grooves 24 formed by projections 25 from which the coolant passes through holes 26 into the interior of the hollow vanes and is pressed by centrifugal force against the surfaces in contact with the hot gases. Vapor formed in the interior of the vanes escapes rearwardly through the holes 26. Preferably the coolant is fed at such a rate that it vaporizes substantially completely in the vanes in order to avoid an accumulation of coolant in the vanes thereby increasing the centrifugal stress on the vanes.

The gases from the blast leave the vanes in a more or less transverse direction, and therefore tend to impinge against adjacent surfaces of the rocket craft. Moreover, the residual velocity of the gases that leave the turbine vanes transversely is likely to be large for single stage turbines and is lost for propulsion. These disadvantages may be eliminated and the residual velocity of the exhaust gases utilized for propulsion by the provision of suitable guides or redirectors 21 shown in greater detail in Figs. 8, 9 and 10. The deflectors comprise a collector portion 28 within which are straightening vanes 29 for removing eddies, and a main body portion 30.

Since the deflectors are heated constantly, cooling means is essential. Cooling may be effected advantageously :by constructing the deflector with hollow wall portions and hollow vanes, and introducing and removing a coolant, such as water, through hollow supports 3 I. In order to provide additional cooling for the vanes 29, inclined or substantially tangential holes 32 are pierced just under the forward edges of the vanes. By this means a thin sheet of coolant may be kept flowing between the blast and the adjacent surfaces of the vanes.

The redirectors are preferably constructed of a metal not only having high strength at elevated temperatures but also good thermal conductivity so that heat concentrated at any particular location will be rapidly conducted to the adjacent coolant.

When the turbine blades extend over a smaller portion of the periphery of the blast than in Figs. 1 to 4, it is desirable to provide separate redirectors for each end of the turbine blades as shown at 33 in Fig. 5, which shows a shorter form of turbine blade 22'. An enlarged fragmentary view and an enlarged sectional view of this form' of turbine blade are shown in Figs. 6

and 7. respectively. These figures show in particular an-advantageous shape-of the blades'to direct the impinging gases laterally outward to each side of the blades. v

In order to obtain large variations in thrust, the turbine blades may be swung into and out of the periphery of the rocket blast byrotating the bases l8 about the pivot points at i9. This may be effected by means of pinions 43 engaging fixedracks 44 and actuated by reversible meters 45 fastened to bases l8. To accommodate such movement of the assemblies flexible bellows 46 and 41 are provided in the outlet pipes. li'and the intake pipes II, respectively.

Because of the relatively largeinertia of the system, however, this method is not suitable for controlling rapid and comparatively small variations in pressure. Rapid pressure control, which is of importance not only in maintaining constant thrust but also in making possible rapid variations in thrust, may be obtained by means shown in Fig. 16. The bellows operator 54 which is connected to a pressure fluid tank, not shown, through pipe 54' and two-way valve I30 shown in Fig. 16a can control the valve members independently of the compression springs 53, by means of valve rods 58 connecting the end plate of the bellows to'the valve member. As shown in Fig. 16a pressure in bellows operator 54 may be controlled by valve I30 which may be actuated by remote-controlled motor II to connect pipe 54" to a fluid pressure tank through pipe I32 or to atmosphere through pipe I33. Instead of -controlling the two by-pass valves of a single motorturbine-pu'mp assembly as shown in Fig. 16, a bellows operator or other means'for. positively actuating the by-pass valves, may be connected to all of the'by-pass valves in the rocket craft,

or a separate operator may be provided for each by-pass valve.

Owing to the fact that the blast gases impinge against one side only of the turbines, it isdesirable to provide means for neutralizing the resultant radial force on the bearings 60, 6| (Figs. 11 and 12), due'to this unbalanced force on the turbine. Moreover, such counterbalancing should be constantly equal to the turbine force, even when the latter varies, as otherwise there will bea large unbalanced radial force on the bearings which is undesirable because of the high speed of the pumps. This counterbalancing is eflected by means of compensator block 42 and associated devices. The block 42, through which shaft l5 passes, hasin its bottom portion a cylindrical boring 62 penetrating to the shaft. Plunger 63 which is slidably mounted in boring 62 bears at its pointed lower end in a slight depression 64 in base l8, which serves to prevent sliding of the block 42 along the shaft.

A tube 65 allows air, oil or any suitable pressure fluid to enter the boring 62 between plunger 63 and the shaft. The block 42 fits closely around shaft i5 and a groove 66 containing flexible packing is cut in the block around the inner end of boring 62. Outside of groove 66 is a second groove 81. A drain 81' extends from groove 81 to the outside atmosphere to drain oil the pressure fluid which seeps past the packing in groove 88.

narrow annular area between boring 62 and the packed groove 86 together with apart of the width of the packing. This force will be small, however, because of the smallness of the area involved.

The radial force on the shaft produced by plunger-63 is automatically maintained equal to the radial force on the turbine. This is desirable, as iseexplained above, for the reason that the unbalanced turbine force is very considerable and the speed of the shaft is high. A reduction of the resultant force in the bearings to a small amount makes possible the use of small light bearings, running with but little loading either end or radial.

Two small bellows 68, is fastened together andintercommunicating at' their abutting ends, are supported from bearing housing 4| by yoke 10, likewise attached to the bellows at their abutting ends, so that the opposite ends of the bellows are free to move and fluid pressure can pass freely between the two bellows. The outer ends of the bellows are supported on fixed brackets I I, 12 projecting from mounting I3 attached to base l8. Integral with yoke 10 is a valve rod 14, inside thebellows, which can push open a normally spring-closed valve 15.

When the shaft is pushed downwardly by the action of the blast on the turbine, the flexibility of the relatively thin web 40, which supports the pump and turbine unit on the base, permits the valve rod 14 to open valve 15 and thus allows pressure fluid supplied by tube 16, from a tank not shown, to pass into the bellows and through tube 65 into boring 62. The pressure fluid continues to flow into the boring until the bending of the shaft by the turbine force has been overcome. If the turbine force should drop below the compensator force, the excess pressure will bleed off through tube 61'.

Even though the compensator 42 produces a lateral, or radial, force L2 on the shaft, equal and opposite to that on the turbine L1, (Fig. 13), there will remain a moment of force on the shaft equal to either force times the distance between the compensator block 42 and the turbine, and hence there will still be radial forces on the bearings 60, 6|. Complete compensation may be provided by supplying one additional force Lo by means of a plunger 80 sliding in a block 8! similar to 42 but abutting a fixed member 82. In this arrangement the force L: must be greater than the force on the turbine L2 by the amount of the added force In.

An alternative arrangement, indicated in Fig. 14, is somewhat less desirable in that it introduces two additional forces instead of one. The force L2 is, however, no greater in this case than Li. In this arrangement the two additional forces La, L4 form a couple equal and opposite to the couple provided by L1, L2. The additional forces La and L4 can be made small if the distance provided by means of a nozzle 83 (Fig. 1'7) supplied with high pressure gas from tank 84 controlled by pressure reducing valve 85 and solenoidoperated valve 86. For a single start, the pressure gases may be provided by a relatively slowburning powder charge 81 in a nozzle chamber 88 (Fig. 18). The charge may be flred electrically or by any other well known means.

Inasmuch as most of the energy of the blast from the rocket motor passes through the central I portion of the blast without impinging upon the turbines, it is desirable, in order to build up rapidly andefilciently to operating conditions, to deflect most of the rocket motor blast to the turbines during the starting period. This may be effected by starting deflectors 90 (Figs. l920). The deflectors comprise narrow side plates or shrouds 9| to confine the blast to the turbine, and a deflector blade 92. The deflectors are pivotally mounted to swing about the turbines. At starting they are held by coil springs 93 in position (full lines in Fig. 19) to direct the full blast to the turbines until the blast pressure builds up sufficiently to push them outwardly about pivots 94 to the position shown in dotted lines where they are caught and retained by spring catcher 95 until released, in any suitable way, for another starting operation.

Fig. 21 shows an arrangement in which the turbines I3 are mounted at right angles to the arrangement of Figs. 1-3. This is particularly useful if more than one pump is to be driven by one or more of the turbines as at I4.

In Fig. 22, the turbine-pump assembly of the invention is shown mounted at the rear end of a rocket craft, two of a group of four rocket motors being shown. Parts corresponding with parts of Fig. l are indicated by the same reference numerals.

Fig. 23 shows an automatically counterbalanced end thrust turbine-pump assembly embodying the principles of the invention. The peripheral portion of the blast from rocket motor I impinges on blades I02 (shown diagrammatically in radial aspect in Fig. 24) of turbine IOI.

Three pumps, I03, I04, I05, are shown around a single shaft H0, the three respective impellers being keyed to the shaft. The bearings I06 are preferably of the carbon sleeve type held in steel collars Ill'l shrunk on, with a narrow self-aligning part engaging a support ring I08.

The downward or rearward thrust due to the motor I00 will be considerable, and with more than one motor will not only be greater, but will be variable, if a variable number of motors is used, in order to secure a varied thrust on the craft in question.

End thrust must be avoided, both because of magnitude and variability, and this is accomplished by using high, but varying, pressure from the outlet pipe III of pump I03, this pressure passing through tube I I2 to a variable valve I I3, shown in greater detail in Fig. 25, and thence through the tube H4 to an annular recess H5 in the pump casing I03. Liquid pressure is thereby exerted on the under or rear side of the ring on the flange I I6 integral with the shaft.

Whatever leakage takes place is caught in two annular grooves H1, one on each side of the flange H6, these being connected together by a short tube or passage I I8, and thence to a drain, or to the intake pipe H9 of the pump I03.

The pressure in the recess H5 is controlled by 4 a sensitive contact maker consisting of a pivoted lever I20 having a fork at the free end which engages a narrow flange I2| on the shaft H0. As the force on the turbine Illl increases or decreases, contacts are made at I22 which cause the relay I23 to widen or reduce the valve opening in H3, preferably by solenoids operated by I24 in any well known manner. The valve H3, as shown in Fig. 25, comprises a valve element I34 movable to open or close the valve passage under the action of opposed solenoids I35, I36 con trolled by contacts I22. Leakage past recess H5 makes it possible to reduce the pressure in the recess quickly by reducing the flow of liquid through valve H3.

I claim: A

1. An auxiliary power device for gas blast propelled craft comprising a plurality of turbines mounted on the craft with the blades of said turbines engaging symmetrically disposed peripheral portions only of the propulsion blast.

2. An auxiliary power device for gas blast propelled craft comprising a plurality of turbines mounted on the craft and positioned with the blades thereof engaging symmetrically disposed peripheral portions only of the propulsion blast, and means for varying the amount of engagement of the turbine blades with the propulsion blast.

3. An auxiliary power device for gas blast propelled craft comprising a plurality of turbines mounted on the craft with their axes substantially normal to the axis of the propulsion blast and positioned with the blades thereof engaging symmetrically disposed peripheral portions only of the propulsion blast.

4. An auxiliary power device for gas blast propelled craft comprising a turbine mounted on the craft with its axis substantially normal to the axis of the propulsion blast and positioned with the blades thereof engaging the peripheral portion only of the propulsion blast, the blades of said turbine being shaped to conform substantially to the periphery of the outlet nozzle through which the blast is discharged.

5. An auxiliary power device for gas blast propelled craft comprising a plurality of turbines mounted on the craft with their axes substantially normal to the axis of the propulsion blast and positioned with the blades thereof engaging symmetrically disposed peripheral portions only of the propulsion blast, the blades of said turbines being shaped to divert propulsion blast gases impinging thereon laterally outward to each side of the turbine rotors.

6. An auxiliary power device for gas blast propelled craft comprising a plurality of turbines mounted on the craft with their axes substantially normal to the axis of the propulsion blast and positioned with the blades thereof engaging symmetrically disposed peripheral portions only of the propulsion blast, the blades of said turbines being shaped to divert propulsion blast gases impinging thereon laterally outward to each side of the turbine rotors, and guide means positioned to engage the gases leaving the turbine blades and shaped to redirect said gases in the direction of flow of the propulsion blast.

'7. An auxiliary power device for gas blast propelled craft comprising a plurality of turbines mounted on the craft with the blades of said turbines. engaging symmetrically disposed peripheral portions only of the propulsion blast, and means movable into the propulsion blast between said turbines to direct substantially the entire blast into engagement with the blades of said turbine.

8. An auxiliary power device for gas blast propelled craft comprising a plurality of turbines 9 mounted on the craft with the blades of said turbines engaging symmetrically disposed peripheral portions only of the propulsion blast, means movable into the propulsion blast between said turbines to direct substantially the entire blast into engagement with the blades of said turbine, means efiective to urge said directing means into the propulsion blast only at low blast velocities, and means for engaging and holding said directing means out of the propulsion blast at high blast velocities.

9. In a gas blast propelled craft having a streamline cowling, an auxiliary power device comprising a turbine mounted on the craft with its axis substantially normal to the axis of the propulsion blast and positioned with the blades thereof engaging the peripheral portion only of the propulsion blast, the blades of said turbine being shaped to divert propulsion blast gases impinging thereon laterally outward to each side of the turbine rotor, and guide means positioned to engage the gases leaving the turbine blades and shaped to redirect said gases in the direction of flow of the propulsion blast, the turbine and guide means being positioned in a recess within said streamline cowling to be shielded by said cowling from the slip stream along said cowling. ROBERT H. GODDARD.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number OTHER REFERENCES The Problem of Rocket Fuel Feed, in Astro- V 5 nautics, June 1936, pages 9-12. 

